Exhaust gas heated system for engine intake manifold



March 1965 J. B. PLATNER ETAL 3,171,393

EXHAUST GAS HEATED SYSTEM FOR ENGINE INTAKE MANIFOLD Original Filed June 15. 1960 l 4 Sheets-Sheet 1 INVENTORS JOHN B. FLA TNER 0N0 H DRE J. E. ROUALEI Mam March 2, 1965 J. B. PLATNER ETAL 3,171,393

EXHAUST GAS HEATED SYSTEM FOR ENGINE INTAKE MANIFOLD Original Filed June 13. 1960 4 Sheets-Sheet 2 March 1965 J. B. PLATNER ETAL 3,171,393

EXHAUST GAS HEATED SYSTEM F OR ENGINE INTAKE MANIFOLD Original Filed June 13. 1960 4 Sheets-Sheet 3 JOHN 5. FLA TNR mvn l"T Tl AN RE J.E.ROU/7LE7.- i I P E? I I INVENTORS Mardl 1965 J. B. PLATNER ETAL 3,171,393

EXHAUST GAS HEATED SYSTEM FOR ENGINE INTAKE MANIFOLD Original Filed June 15. 1960 4 Sheets-Sheet 4 04 INVENTOR L TNE iii/715g fsfi L/ub'z' M United States Patent 3,171,393 EXHAUST GAS HEATED SYSTEM FOR ENGINE INTAKE MANIFOLD John B. Platner, Detroit, and Andre J. E. Ronalet, Birmingham, Mich, assignors to Chrysler Corporation, Highland Park, Mich., acorporation of Delaware Original application June 13, 1960, Ser. No. 35,634. Divided and this application Feb. 7, 1964, Ser. No.

3 Claims. (Cl. 123-55 This invention relates to internal combustion engine intake systems provided with exhaust gas heating means for heating the charge prior to delivery to the cylinders of the engine and to exhaust gas heating systems for effecting this result. It particularly relates to heating systems of this type for V engines.

The present application is a division of our copending application Serial No. 35,634, filed June 13, 1960.

In currently made V engines for passenger vehicles it has been customary to provide an intake manifold intermediate the opposite cylinder banks of the engine with one or more carburetor sources of air-fuel mixture for charging the cylinders and to provide a hot spot on the intake manifold to heat a portion of the intake manifold passage system with exhaust gases caused to flow between the exhaust manifolds of the opposite banks through passages in the cylinder heads connecting therewith and with the intake hot spot.

The present invention is particularly concerned with an air ram type intake system for V engines having opposite outboard carburetor fed plenum chamber sources of airfuel mixture, one positioned outboard of one cylinder bank and the other outboard of the opposite bank, each provided with a hot spot whereby the charge fed to such chambers is heated by exhaust gases before being distributed to conduits conducting the charge to cylinders of the bank opposite that to which the chamber is immediately outboard. Moreover, the invention is directed to an arrangement of this character having an exhaust system and controls whereby the exhaust gases of an entire bank of cylinders may be directed to one hot spot without passage across the engine and the flow thereof is automatically controlled to control such flow to the hot spot at predetermined engine temperature.

An object of the invention is to provide an exhaust gas intake hot spot heating system including conduit means for conducting exhaust gases from an exhaust manifold to the hot spot and from the hot spot to the engine exhaust pipe, wherein heat responsive valve means is provided operable in one position for inhibiting flow of exhaust gases directly from the exhaust manifold to the engine exhaust pipe and in a second position to inhibit flow of exhaust gases from the connecting conduit means between hot spot and exhaust pipe to the exhaust pipe.

A further object is to provide a heating system as in the preceding object wherein the heat responsive valve means in said second position also inhibits flow of exhaust gases between said exhaust manifold and the connecting conduit means between exhaust manifold and hot spot.

An additional object is to provide an exhaust gas intake hot spot heating system including a first conduit means for conducting exhaust gases from an exhaust manifold to the hot spot, a second conduit means for conducting exhaust gases from the hot spot to an engine exhaust pipe connected with the exhaust manifold and wherein a heat responsive valve means is provided in said exhaust pipe above the connection of said second conduit means with the exhaust pipe for controlling flow between the manifold and exhaust pipe and wherein a second controllable valve means is provided in the first conduit 3,171,393 Fatenteci Mar. 2, 1965 ICC means for controlling flow between the exhaust manifold and hot spot and which valve means may be interconnected such that one valve means is open when the other is closed.

Other objects and advantages of our invention will appear from the following description and from the drawings wherein:

FIGURE 1 is an elevational view partly in section of a V engine showing the intake hot spot heating system of the invention as applied thereto;

FIGURE 2 is a plan view of an eight cylinder engine of the V type shown in FIGURE 1 to which the invention is applied;

FIGURE 3 is an enlarged elevational view of a portion of the right hand bank of the engine of FIGURES 1 and 2 showing one form of the invention applied thereto;

FIGURE 4 is a similar view of the left hand bank;

FIGURE 5 is an elevational view of a portion of the right hand bank of FIGURE 1 showing a hot spot modification arranged to primarily heat the air-fuel mixture from the primary throttle of a four-barrel carburetor;

FIGURES 6 and 7 are side elevational views of the engine in FIGURE 4 showing modifications in the manner of controlling the exhaust gas flow; and

FIGURE 8 shows a modification applicable to all the forms of the invention of FIGURES 1 to 7 wherein the hot spot is under the primary throttle only.

Referring now to the drawings wherein our invention has been illustrated as embodied in a V-8 engine provided with a long branch tunable intake system capable of dynamic charging by harmonic resonant tuning and by mass movement of air in the cylinders and wherein similar numerals are used to designate similar parts of the structure, FIGURE 1 shows a V engine having opposite banks 9 and 9a of cylinders 10 arranged at a suitable angle to each other and forming an angle of to each other on a cylinder block 11, in FIGURE 1.

The cylinders 10 of each bank are preferably aligned longitudinally of the engine as schematically illustrated in FIGURE 2, with the cylinders of the opposite banks offset longitudinally relative to each other. For convenience of reference, the cylinders of the left hand cylinder bank 9 which is to the left looking forwardly from the flywheel end of the engine are numbered 1, 3, 5, and 7 starting such numbering at the opposite or fan of the engine, and those of the right hand bank are numbered 2, 4, 6, and 8 respectively, these numerals appearing internally of the cylinder representations in FIGURE 2.

Secured to the block 11 are left and right cylinder heads 12 and 12a respectively, each provided with suitably shaped combustion chambers 13 shown to be of the wedge type, immediately above each cylinder 10. These may, of course, be of other shape, for instance, hemispherical.

Each cylinder has a piston 14, reciprocable therein and operably connected to a crankshaft 15 through a connecting rod 16 and wrist pin 17. Crankshaft 15 may be of any type, but will preferably be of the 90 type described in Patent No. 2,766,743 making possible various firing orders there described, for example, 184-36 5-7-2.

The combustion chambers or cavities 13 of the cylinders 10, are provided with a single inlet opening or port 20 closed by an inlet valve 22, and with a single smaller exhaust outlet or port 24 closed by an exhaust valve 26, these ports and valves as evident from FIGURE 2 being aligned longitudinally of the engine and as shown with the inlet ports of cylinders 1 and 3, 5 and 7, 2 and 4, and 6 and 8 in juxtaposition. Other valve arrangements such as shown in the patent are also contemplated. Each chamber is preferably fired by a single sparking means 27 projecting therein, as seen in FIGURE 1, and preferably located intermediate the valves 22 and 26.

3 The inlet and exhaust valves of both banks are preferably'operable from a common camshaft 28 located above the crankshaft 15, it operating hydraulic tappets 30 and thereby the push rods 32 and 34 engaging the inlet and exhaust'valve rocker arms 36 and 38 respectively, actuate respectively the normally spring-40-held closed valves 22 and 26. V I

The cylinders of the opposite banks are fed with a can bustion charge by a long branch carburetor fedintake i:

system generally designated by the numeral comprising a section 52 for feeding the left bank of cylinders having a mounting flange 54 by which it is secured through "bolts 56"to the inner face 58 of the head 9 of the left bank and an independent separate substantially identical secnon 5 2a for'fe'eding the right hand bank similarly secured by a flange and bolts to the inner. face 60 of the right hand bank. 7

The section 52 comprises a plenum chamber ordistribution box 62 whose inner compartment 64 is fed with air and fuel by a suitable'carburetor 66 having any numberof throats, two throats '68, 7Q being shown coinciding with corresponding risers 72, 74 in the top face of the chamber 62 orr which the carburetor is suitably mounted by bolts 76. The plenum chamber 62 is located outwardly beyond the right hand bank and g'enerally below the top of the valve mechanism cover 78a 'of the head 12a. Extending in fan-like fashion from the plenum chamber 62 as seen in FIGURE 2, are a plurality of elongated conduits or passages, one for each cylinder 'of the left bank, four being shown for the V-8 engine here illustrated and numbered 80, 82, 84,.and 86 which extend inpairs 80, 82 and 84, '86

in a generally smooth curve across the engine to connect with intake passages 88 of the cylinders 1, 3, 5, and 7 respectively, inthe head 12 of the left bank, the latter passages startingat the face 58 and terminating at the inlet ports 20 of the eylindersl, 3, 5, and 7 to make lengthy continuous .passages between the plenum chamber 62 and these inlet ports. y I The section 52a like the section 50 comprises a plenum chamber 62a located outwardly beyond the left handbank 9 of-the engine and generally below the top of the valve mechanism cover 78 of this bank. Like the section 52 7 this section also has extending from "the plenum chamber 62a a plurality of elongated conduits ortpassages, one

-for each cylinder of the right hand bank numbered 80a,

82a, 84a, and 86a respectively, which extend in pairs 80a, 82a, and 84a, 86a in a generally smooth curve across the engine to connect with intake passages 88a of the cylinders 8, 6, 4, and 2 respectively, in the. head 12a of the right hand bank, the latter passages starting at the face 60 and terminating at the inlet ports 20 of the cylinders 8, 6,4, "and 2 respectively, to provide lengthy continuous passages between the plenum chamber 62a and these inlet ports. The plenum chamber 62a is provided with risers 72a, -74awhieh connect with corresponding throats of a dual carburetor 66a seated on this chamber.

It will be noted that the paired conduits ofthe two sec- -tions 52 and 52a interlace and cross each other, as

evident fro'mFIGURES 1 and '2, to form a relatively compactarrangementin which the'paired conduits 84, 86 lie intermediate the conduits 80a, 82a and 84a, 86a and the conduits 84a, 86a lie intermediate the conduits 80, 82 and 84, 86. flanges-54 'of'at least one of the sections-52,-52a, forexample, that of the section'52, is split at the lines 90,9011

-' to form a removable section 90b at the time of making assembly.

As seen in FIGURE 2, -all of-the'conduits of each section lie in substantially the same plane in elevation and each open into their respective plenum'chamber's by a separate apertures also located in thesame 'generalhorizontal plane, as will be seenin FIGURE 2. Moreover, the plenum chambers62, 62a are interconnected by a balance tube 91 whose ends open into the plenum cham- These 7 In order to make this possible, the mounting 7 bers in the same plane as'the conduits and which may for purposes of assembly be made of several sections interconnected with each other so as to provide stub ends on each'of the plenum chambers.

In order to provide for rapid heating of the air-fuel mixture fed to the plenum chambers during cold starting, each of the plenum chambers is provided at the base thereof with a suitable hotspot exhaust gas heating box numbered 94a on the plenum chamber 62a, such boxes providing compartments 96 and 96arespectively, to which .hot exhaust gases may be fed to heatjthe floors 98 and'98a ofthe plenum chamber compartments 64 and 64arespectively. It will be observed that in FIGURES 1 and2, the hot spot heating -boxes'94,= 94a are substantially the full area of the base of the plenum chambers 62, 62a respectively; The leftha'nd'b'ank of the engine, as seen in FIGURES 1, 2, and 4, has'secured to' the outer face 1000f its head 12am exhaust "manifold generally designated by the numeral 102 and which comprises arunner or header section 104 provided with lateral branches 106 connecting the header with exhaust passages 103 forming 'continuations of the lateral bra'nches106 in'the head 12 and terminating at the exhaust ports 24 in such head. The header -104has a downwardly extending lateral branch conduit '110'located generally centrally of the header longitudinally'of the engine and terminating in a flanged connection 112 with an exhaust pipe 114 which in turn connects'with a-muflier 116,- all as seen in FIGURES l and 4.

The right hand bank' of the engine, as seen in FIG- URES 1, 2 and 3 has asimilar exhaust manifold generally designated by the numeral 102a as in the case of the left 'hand exhaust manifold havinglateral branches 106a-conmeeting with the exhaust passages 108a of the head 12a of that bank. The manifold 102a also has a downwardly directed lateral discharge branch 110;; which, as shown in FIGURE 3, is located at the rearward end of the engine.

It'will be understood that this discharge branch may, if

"desired, be located similar to that of the manifold 102 in the mid region of the header 104a. The discharge con du it 110a also, terminates in a flanged connection 112a with an exhaustpipe 114a connection,'as seen in FIGURE 1, with a mufiler 116a.

vIt will be apparent from the above description of the exhaust manifold system that each 'bank has its own exhaust system to which the exhaust gases of all the cylindersof an entire bank are delivered and conducted away to a separate muffler. It will be understoodjj'however, thatthe exhaust pipes 114 and 114a inFIGURE '1 may, if desired, begjoined' in a single'pipe connected to a single 7 muffler.

- plenum chamber szaef'the intake section 52a feeding the cylinders 2,4, 6, and of the right hand bank is connected to the exhaust 'rnanifold system of the left hand bank by means of the conduits 120, 122.

As seen in FIGURES 11 and 4, the conduit 120 interconnects the compartment 96a of thehot spot 94a and the header 10401: the left hand, exhaust manifold by an elbow conduit connection of suitable-characterwhich opens into the floor of the compartment 96a and into the exhaust manifold runner 104 -at the outer upper side thereof interthe lateral conduit'110 of the exhaust manifold "102, as

openmg--1ntoas1de wall 1-24 of the hot spot-94m, I I

seenin FIGURES 1, 4, and 6, conduit 122 preferably It will be noted-that the connectionofconduit 120 with the compartment 96a is at one end thereof, as-seen in FIGURE4, while the connection-ofthe conduit122 is at 75-the opposite'endthereof. Such an arrangement is preferred in order to facilitate movement of the exhaust gases entering the compartment 96a through the conduit 120 from the exhaust manifold to scrub across the floor 96a of the plenum chamber 62a and give up its heat thereto before discharging into the conduit 122.

A thermostatically controlled heat valve generally designated by the numeral 126, is provided in the discharge conduit 110 of the exhaust manifold 102 and arranged such that its throttle blade or valve 128 is movable with a rocker shaft 130 controlled by a metallic spring and counterweight, not shown, to move between two positions, one a horizontal position as shown in FIGURE 4 in the full lines closing off the passage in the conduit 110 between the exhaust pipe 144 and the exhaust header 104, and the second a vertical position shown in phantom in this figure closing off the connection of the conduit 122 with the conduit 110.

The right hand bank is provided with a similar interconnection between its exhaust system 1020 and the hot spot 94 of the intake section 52 which feeds the left hand bank. Thus as seen in FIGURE 3, a conduit 120a similar to the conduit 120 of the left hand bank interconnects the heating compartment 96 of the hot spot 94 with the exhaust manifold header 104a, and a second conduit 122a interconnects this compartment 96 with the lateral conduit 110a of the exhaust manifold 102a immediately blow a thermostatically controlled heat valve generally identified by the numeral 126a, whose throttle blade 128a and shaft 130a are operated between two positions, one a horizontal position, as shown in full lines wherein the blade 128a closes 01f connection between the header 104a and the exhaust pipe 114a, and a second vertical position shown in phantom wherein the blade 128a closes off the connection between the conduit 122a and the conduit 110a.

In operation of the hot spot heating system here described, the heat valves 126 and 126a will normally be in their position shown in FIGURES 3 and 4 closing off the conduits 110 and 110a from the exhaust pipes 114 and 114a respectively, when the engine is cold. When the engine is started and operating, the exhaust gases from the four cylinders of the left hand bank will be unable to -dis charge except by leakage out the conduit 110 and will instead flow through the conduit 120 upwardly into the heating compartment 96a across the floor 98a of the plenum chamber 62a and out the conduit 122 into the exhaust pipe 114. Similarly, the exhaust gases of the right hand bank will flow from the exhaust manifold 102:: through the conduit 128a into the compartment 96, scrub the floor 98 of the plenum chamber 62 and flow out of the compartment 96 through conduit 1220: into the exhaust pipe 114.

During warmup of the engine the heat valves 126 and 126a will be positioned to provide optimum heating of the hot spot. This is usually the fully closed position of the valves as shown in FIGURES 3 and 4. However, it will be understood that the valves may be arranged for a partially open position during this operating cycle.

When the engine is fully warmed up and depending upon the vehicle operating conditions, the heat imparted to the control valves 126 and 126a from the exhaust manifolds and the air flow past the valves will control the positioning of the thermostats of the valves and blades 128, 12812 and thereby determine the heat input to the hot spots 94 to give optimum operation of the engine. This may mean an intermediate open position or fully open position of the valves.

Referring to FIGURES 3 and 4, it will be observed that when the valves 126 and 126a will have moved their operating blades 128 and 128a respectfully to the fully open position shown in phantom in FIGURES 3 and 4, that the exhaust gases of the four cylinders of each bank will flow from the manifolds directly out of their lateral conduits 110 and 110a respectively, into the exhaust pipes 114 and 114a respectively, with no flow except for slight leakage occurring between the exhaust manifolds of the banks and the heating compartments 96 and 96a of the plenum chamber hot spots. In this connection it will be noted that the exhaust gases may then flow into the compartment and through the connecting conduits but will be stopped by the throttle blades 128, 128a of the heat valves which close off the ends of the conduits 122 and 122a respectively.

Referring now to FIGURES 5 and 6 which show a modification of the structure of FIGURES 1-4 inclusive, it will be noted that as in FIGURES 3 and 4 the discharge pipe 122 extends between the hot spot 94 and the conduit and has its end, which opens into the conduit 110, closed by the throttle blade of the heat valve. As previously stated, however, there may be a slight flow of exhaust gas due to leakage, in the arrangement of FIGURES 3 and 4 from the exhaust manifold through the hot spot and conduit 122 past the heat valve. In FIGURES 5 and 6 this leakage flow is more positive prevented by extending the conduit 121) between the hot spot 94 and a chamber 149 formed in the conduit 110 instead of having the conduit connect with the runner portion 104 of the exhaust manifold, as in FIGURE 4. It will be noted that the chamber 146 here is of substantially rectangular section having side walls 142, 144 and end walls 146, 148 as seen in FIGURE 6, a top wall 150 and a bottom wall 152, as seen in FIGURE 5. This chamber 140 except for the wall 144, forms a lateral extension of the circular conduit section 118.

As evident from FIGURE 6, the wall 144 reduces the normal circular section of the conduit 110 to a D shape, this wall 144 blending into the runner section of the manifold in the same manner as the remaining portion of the circular section with a smooth curve portion 154. As seen in FIGURE 5, the wall 144 preferably provides a lip 156 against which the throttle blade of the thermostatically controlled heat valve, generally designated by the numeral 158, and rotatable on a pin axis 160, may abut to close off the chamber 140 from the conduit 110. The throttle blade, as seen in FIGURE 5, has a portion 162 which in its horizontal position shown in FIGURE 5, extends across the open section of the conduit 110 and is similarly shaped to fill the same, and has a portion 164 which is a continuation of the portion 162 but on the opposite sides of the axis which substantially abuts against the bottom wall 152 of the chamber 140.

In this position of the throttle blade 158, the exhaust gases emanating from the exhaust manifold through the conduit 110 will, instead of passing out through the exhaust pipe 114, be directed by the throttle blade into the chamber 140 and from there through the conduit 120 to the hot spot 94, then through the hot spot to the conduit 122 emptying into the conduit 110 below the throttle blade portion 162. Moreover, when the throttle blade 158 is in its vertical position shown in phantom in FIGURE 5, the portion 164 of the throttle blade will be seated against the lip 156 of the chamber 140 and the portion 162 will be seated against the flat wall portion 166 of the conduit 110 closing off the end of the conduit 122. In this position of the throttle blade it will be apparent that flow of exhaust gases to and from the hot spot is sealed off. Moreover, it will be observed that the lip 156 of chamber 140 projecting as it does within the circular section of the conduit 110 will direct the exhaust gases from the exhaust manifold past the chamber 140 and past the conduit 120. The throttle blade 158 will assist in this action. Manifestly, the modification in FIGURES 5 and 6 may be applied to both banks of the engine, that for the left bank only having been described above.

FIGURE 7 shows a further modification according to which flow of the hot exhaust gases to the hot spot 94 is controlled in the conduit 120 by a valve generally referred to by the numeral 170 and discharge of the gases to the exhaust pipe 114 through the conduit 110 is preferably controlled by a conventional heat responsive butterfly valve generally designated by the numeral 172. When be directly discharged into the exhaust conduit'110 from the exhaustmanifold past the blade 172a of valve 172 which is then in open position.

t It will be understood that the valves 170 and 172 may each be thermostatically controlled independently of each .conduit 120 will be inhibited and thetexhaust gases will I other by conventional bimetallic heat responsive spring 5 elements 172b (see FIG. 6) Preferably, however, the valve 172 will be thermostatically controlled and a linkage connection generally designated by the numeral 172e, provided between the valves 17 t) and 172 such that when the valve 170 is open, the valve 172'will be closed and vice versa when the valve 170 is closed, the valve 172 willbe open. This linkage will generally comprise alever 173 fixed to the shaft extension 174 of the throttle blade 171 of valve 170, a second lever 175 fixed to the shaft extension 176 of the blade 172a of the valve 172 and a link 176 pivotally connecting the ends of these levers which are positioned as shown in FIGURE 7. A feature of the invention is the provision of-a lost motion connection be tween the operating arm or lever 173 for the valve 170 and the valve whereby it is possible to adjust the butterfly 171 of the valve 170 to any prefixed relationin theconduit 120 so as to control the quantity of exhaust gases flowing to the hot spot while at the same time providing a gines of any number of cylinders and such will be apparent to those skilledv in theart. Accordingly, all such modifications coming within the intent and spirit of our invention as expressed in the appended claims is contemplated.

We claim: I t

1. A' V. engine comprising opposite banks of cylinders having intake and exhaust ports, each bank having an exhaust manifold connecting only with the exhaust valve ports 'of the cylinders of that bankga pair of intake manifolds each comprising a plenum chamber adjacent one bank of cylinders and displaced from the exhaust manifold of that bank and having a plurality of induction tubes connecting with this chamber and interconnecting with the intake ports of cylinders in the opposite'bank of cylinders, means supplying a fluid charge to each plenum chamber, a hot spot on the lower side of each plenum chamber, conduit means connecting each said hot spot with the exhaustman'ifold of the bank of cylinders which it is adjacent, discharge conduit means'a'djacent each bank for conducting exhaust gases from the exhaust manifold of that bank, conduit. means connecting each hot spot with the discharge conduit means of the exhaust manifold which it is adjacent, and valve means in each 7 said discharge conduit means forcontrolling the flow of exhaust gas through each said hot spot.

2, A V engine comprising opposite banks of cylinders having intake'and ex'haustports, each bank having an exhaust manifold for receiving hot exhaust gases from the engine cylinders of that bank ,through the exhaust means for completely closing olf flow 'of gas between the I exhaust manifold and the hot spot. For effecting this result the lever 173 is made loose on the shaft 174 and a second lever or arm 177 is fixed to shaft 174. One of the levers 173, 177, preferably the lever 173, is provided as shown with a transversely extending adjustment screw 178 threadedly received in a suitable portion 179 of the lever 173 and which may abut the lever 177 and which is adjusted to provide'a predetermined angular relation between V the two levers. A lock nut 179a may be provided to fix V of lever 175 even after blade 171 is intthe fully closed position of valv'e 170, such being made possible by the spring 180, Where desired, the heat valve l72lmay be.

replaced by one similar to the heat valve 126, as shown in FIGURES 3' and 4, whereby the apertured end of theconduit 122 in the conduit 110 will be closed on when the valve 172 iso'pen. Such will prevent any rearward flow of exhaustgas from the conduit 110 into the hot spot 94. Obviously the modification inFI GURE 7 may also be 'ap plied to both banks of the engine.

FIGURE 8 illustrates a modification of an arrangement similar to that in FIGURES 3 and 4 employing, however, I

a conventional heat valve wherein the hot spot instead of extending completely across the base of the plenum chamber 62,"provides a hot spot 180 only directly below the I 7 primary throttle portion 70 of the carburetor, this provid-' ing a means in certain cases of preventing overheating of the flo'or of the plenum chamber. Manifestly, this feature may also be applied to the constructions FIGURES =1-7 inclusive. I I

Although the features of our invention have been det scribed with respect'to a V engine, itiwill'be understood that the same are applicable to a line engine and to enports thereof, a pair of intake manifolds for delivering a combustible charge to the intake ports of said banks,

a each said intake manifoldcomprising. a plenum chamber in' juxtaposition to one of said; banks of cylinders and having a plu'rality of intake tubes connecting each said plenum chamber with intake ports of the cylinders of the opposite bank of cylinders, means, supplying a fluid charge toe'ach of said plenum chambers, a hot spot on each of said plenum chambers for heating theffluid charge delivered to said intake tubes, discharge conduit means adjacent each bank of cylinders connecting with the exhaust manifold of said bank for conducting exhaust gases therefrom, a second conduit adjacent each bank for interconnecting the hot spot of the plenum chamber adjacent that bank with'one of said exhaust manifold and discharge conduitmeans adjacent the same bank for conducting exhaust gases to said hot' spot, a third conduit means adjacent, each bank for interconneetingrthe hot spot of the plenum chamber adjacent that bank with the said discharge conduit means adjacent that bank, and valve means in said discharge conduit means adjacent each bank operable in one position to permit free flow of exhaust gasffrom the exhaust manifold adjacent that I bank through said discharge conduit means. adjacent that bank" and blocking flow from said third conduit means ad acent-thatbank to said discharge conduit means adjacent that bank and operable in a second'position' to block a free flow of exhaust gas from the exhaust manifold adjacent that ,bank through said discharge .conduit means iadjacentthat bank and permit free flow of exhaust gas throu h said third conduit means adjacent that bank to said discharge conduit means adjacent that bank.

. 3AA V enginecomprising opposite banks ofcylin'ders having intake and exhaust poits, each bank having an exhaust manifold" for receiving hot exhaust ,gases'from the engine cylinders of thatbankthrough theexhaust a ports'thereof, a pair. of, intake'm'anifolds for delivering :a combustible charge to theftintake ports of said banks,

each said intake manifold comprising a plenum chamber in juxtaposition to one of said banks of cylinders and I having a plurality of intake tubes connecting each said 'plenum; chamber with intake ports of the cylinders of the opposite bank of cylinders, means supplying a fluid charge to each ofsaidp len-um chambers, a hot spot at the lower side of each of saidplenum chambers for heat- 9 ing the fluid charge delivered to said intake tubes, discharge conduit means adjacent each bank of cylinders connecting with the exhaust manifold of said bank for conducting exhaust gases therefrom, a second conduit adjacent each bank for interconnecting one end of the hot spot of the plenum chamber adjacent that bank With said exhaust manifold adjacent the same bank for conducting exhaust gases to said hot spot, a third conduit means adjacent each bank for interconnecting the opposite end of the hot spot of the plenum chamber adjacent that bank with the said discharge conduit means adjacent that bank, and valve means in said discharge conduit means adjacent each bank operable in one position to permit free flow of exhaust gas from the exhaust manifold adjacent that bank through said discharge conduit means adjacent that bank and blocking flow from said third conduit means adjacent that bank through said discharge conduit means adjacent that bank operable in a second position to block free flow of exhaust gas from the exhaust manifold adjacent that bank through said discharge conduit means adjacent that bank and permit free flow of exhaust gas through said third conduit means adjacent that bank to said discharge conduit means adjacent that bank.

References Cited in the file of this patent UNITED STATES PATENTS 2,523,611 Clayton Sept. 26, 1950 2,722,203 Drinkard Nov. 1, 1955 2,888,001 Morrish May 26, 1959 2,930,367 Kolbe Mar. 29, 1960 

1. A V ENGINE COMPRISING OPPOSITE BANKS OF CYLINDERS HAVING INTAKE AND EXHAUST PORTS, EACH BANK HAVING AN EXHAUST MANIFOLD CONNECTING ONLY WITH THE EXHAUST VALVE PORTS OF THE CYLINDERS OF THAT BANK, A PAIR OF INTAKE MANIFOLDS EACH COMPRISING A PLENUM CHAMBER ADJACENT ONE BANK OF CYLINDERS AND DISPLACED FROM THE EXHAUST MANIFOLD OF THAT BANK AND HAVING A PLURALITY OF INDUCTION TUBES CONNECTING WIHT THIS CHAMBER AND INTERCONNECTING WITH THE INTAKE PORTS OF CYLINDERS IN THE OPPOSITE BANK OF CYLINDERS, MEANS SUPPLYING A FLUID CHARGE TO EACH PLENUM CHAMBER, A HOT SPOT ON THE LOWER SIDE OF EACH PLENUM CHAMBER, CONDUIT MEANS CONNECTING EACH SAID HOT SPOT WIHT THE EXHAUST MANIFOLD OF THE BANK OF CYLINDERS WHICH IT IS ADJACENT, DISCHARGE CONDUIT MEANS ADJACENT EACH BANK FOR CONDUCTING EXHAUST GASES FROM THE EXHAUST MANIFOLD OF THE BANK, CONDUIT MEANS CONNECTING EACH HOT SPOT WITH THE DISCHARGE CONDUIT MEANS OF THE EXHAUST MANIFOLD WHICH IT IS ADJACENT, AND VALVE MEANS IN EACH SAID DISCHARGE CONDUIT MEANS FOR CONTROLLING THE FLOW OF EXHAUST GAS THROUGH EACH SAID HOT SPOT. 